The killing of a policeman on Paris’s Champs Elysees, claimed by the Daesh terror group, rocked France’s presidential race on Friday with just two days to go before one of the closest races in recent memory.

Bloodshed had long been feared ahead of Sunday’s first round of voting after a string of terror attacks since 2015, and shooting on the world-renowned boulevard forced security to the top of the agenda in the campaign, AFP reported.

Three of the four frontrunners – far-right leader Marine Le Pen, centrist Emmanuel Macron and conservative Francois Fillon – called off campaign events planned for Friday in the wake of the attack.

Le Pen, widely seen as taking the hardest line on security, called for France to “immediately” take back control of its own borders from the European Union and deport all foreigners on a terror watch list.

Macron, a 39-year-old moderate whom other candidates have portrayed as too inexperienced to protect France against the terror threat, warned against any attempts to use the attack for political gain.

“I think we must one and all have a spirit of responsibility at this extreme time and not give in to panic and not allow it to be exploited, which some might try to do,” he told French radio.

The gunman opened fire with an automatic weapon on a police van at around 9:00 p.m. (1900 GMT) on Thursday, sending tourists and visitors running for their lives.

After killing the officer and injuring two of his colleagues just a few hundred meters from the Arc de Triumphe, the gunman was shot dead in return fire while trying to flee on foot.

A statement by Daesh’s propaganda agency Amaq said the attacker was one of its members identifying him as “Abu Yussef the Belgian”.

But French authorities said the perpetrator was a 39-year-old Frenchman living in the Paris suburbs, whose name they did not release.

The Daesh claim raised initial concerns that a possible second attacker could be on the loose.

On Friday, French authorities said a suspect sought by Belgium police, who was suspected of having planned to travel to France on Thursday, had handed himself in at a police station in the Belgian city of Antwerp.

French Interior Ministry spokesman Pierre-Henry Brandet said it was “too early to say” if the man was linked to Thursday night’s shooting.

During a search of his home, Belgian police found weapons, balaclavas and a train ticket for France leaving Thursday morning.